Stem cells block diabetes

Researchers have demonstrated for the first time that the progression of type 1 diabetes can be halted – and possibly reversed – by a stem cell transplant that preserves the body’s diminishing ability to make insulin, according to a study to be published today.

The experimental therapy eliminated the need for insulin injections for months or even years in 14 of 15 patients were recently diagnosed with the disease. One subject, a 30-year-old man, hasn’t taken insulin since his stem cell transplant more than three years ago, according to the study in the Journal of the American Medical Association.

The study suggests a new avenue for treating the intractable disease, in which the immune system destroys insulin-producing beta cells in the pancreas. Without insulin, patients can’t metabolize sugar and run the risk of developing nerve damage, cardiovascular disease, kidney failure and blindness.

Patients with type 1 diabetes typically compensate by monitoring their blood sugar levels every few hours and injecting themselves with insulin as often as five times a day.

After the stem cell treatment, “patients are absolutely medication-free – they’re off insulin,” said Dr. Richard Burt, senior author of the study and chief of the division of immunotherapy at Northwestern University’s Feinberg School of Medicine in Chicago.

The strategy is similar to an approach that has shown some success in treating other immune-system disorders, such as rheumatoid arthritis, lupus and multiple sclerosis.

“We all realize that without addressing the problem at the level of the immune system, we’ll never really beat type 1 diabetes,” said Dr. Francisco Prieto, who treats diabetics in his Elk Grove, Calif., practice and wasn’t involved in the study.

Burt and his colleagues cautioned that they don’t yet know whether the treatment’s effects are permanent and if not, how long they will last. One of the subjects was insulin-free for one year but relapsed after a respiratory viral infection, said lead author Dr. Julio Voltarelli, associate professor of medicine at Ribeirao Preto Medical School at the University of Sao Paulo in Brazil.

The Juvenile Diabetes Research Foundation in New York estimates that as many as 3 million Americans have type 1 diabetes. Between 30,000 and 35,000 new cases diagnosed each year.

The stem cell approach mirrors the bone marrow transplants used to treat patients with certain cancers and blood diseases, wiping out the faulty immune system and replacing it with a new one that functions properly.